Shorty headers will deepen the exhaust note, but there are currently few options available for the 3.7. I am waiting for someone to make stainless shorties. LT headers require an aftermarket X pipe which is available with or without catalytic converters. LT's typically amplify the V6 raspiness. Some people are running LT's, catted X, and resonators ahead of the mufflers and that cuts down on the rasp. This setup will require a tune.
2013 V6 Base Coupe - Performance and Tech Packages - Ingot Silver
Bama Tuned with Airaid CAI - GT front brake upgrade - More to come.